Reduced prevalence of serum antibodies against adeno-associated virus type 2 in patients with adult T-cell leukaemia lymphoma

Seroepidemiological studies have shown previously that cancer patients are less likely to have antibodies against the tumour suppressive adeno‐associated virus (AAV) than control groups. To examine the influence of AAV infection on the development of adult T‐cell leukaemia lymphoma (ATLL), an endemic disease in Southern Japan that is caused by infection with the human T‐cell leukaemia virus type 1 (HTLV‐I), the prevalence of serum antibodies to AAV type 2 (AAV‐2) was tested in healthy HTLV‐I carriers (n = 39) and patients with ATLL (n = 31). The results showed a significant difference in AAV‐2 seropositivity between the two groups: Only 29% of the ATLL patients had IgG antibodies against AAV‐2, whereas 84.6% of the healthy HTLV‐I carriers were seropositive. Analysis of total serum IgG and antibodies against the Epstein‐Barr virus (EBV) EBNA1 antigen showed that the lack of AAV antibodies in patients was not due to an ATLL‐associated immune deficiency. The lower level of AAV‐2 seropositivity in ATLL‐patients may indicate that AAV‐2 antibody‐positive HTLV‐I carriers might be less likely to develop ATLL or that loss of AAV‐2 antibodies may parallel the development of disease. J. Med. Virol. 65:185–189, 2001. © 2001 Wiley‐Liss, Inc.